Many lawn maintenance tools—such as chainsaws, string trimmers, hedge trimmers, blowers, tillers, and the like—include an internal combustion engine as the primary power source for powering the tool. These engines can be single-cylinder, two-cylinder, or even 4-cylinder engines, and these engines can often generate noise levels that are unsafe for the user as well as disruptive to the surrounding communities during use. Landscapers as well as homeowner-users will often wear soundproof or sound-dampening headphones or other ear protection to counteract the noise generated by the engines of the tools.
These lawn maintenance tools also sometimes include an air filter or an air box having a filter located therein, wherein the air filter or air box includes an air filter. However, when these air filters/air boxes are used on small engines, these engines can produce fuel backflow, or “spit back,” wherein unburned fuel that is introduced into the combustion cylinder of the engine travels upstream through the carburetor and into the air filter or air box. This unburned fuel can pool within the air box if it does not flow back into the combustion chamber during the downstroke of the piston, which generates a “sucking” of air through the carburetor.